The identification of biomarkers specific to a particular disease provides a means to better diagnose the disease condition and aids in the design and testing of drugs in clinical trials. Biomarkers specific to amyotrophic lateral sclerosis (ALS) remain unknown, thus limiting our ability to provide a more rapid disease diagnosis. In addition, the lack of ALS specific biomarkers necessitates the use of clinical assessments such as muscle strength indicators and respiratory function measurements to test potential drug benefits in clinical trials of ALS patients. Such measurements may be poor outcome determinants to identify individual drugs that may have limited but positive affects, thereby greatly limiting our ability to identify the best drug combination for maximal patient benefit. Our proposed study will identify ALS specific biomarkers from the cerebral spinal fluid. We hypothesize that a proteomic analysis of cerebral spinal fluid (CSF) from ALS patients and control subjects will identify quantitative and qualitative disease-associated protein changes. Our specific aim is to utilize mass spectrometry based proteomic techniques to identify specific protein biomarkers that occur in ALS patients, thus identifying a novel biomarker signature for ALS. A panel of ALS specific biomarkers is critical for early disease detection and more efficient clinical trials. Our preliminary findings demonstrate the ability to identify mass spectral peaks in the CSF that are diagnostic for ALS. We have identified a panel of 13 putative ALS specific biomarkers. Our proposed studies will both further characterize these putative biomarkers and examine alterations in the proteomic biomarker signature pattern of ALS during disease progression. [unreadable] [unreadable]